NO. 2022. NEW STARFISHES FROM THE PHILIPPINES— FISHER. 221 



SOLASTER TROPICUS, new species. 



Rays 9 or 10. R = 145 mm., r=53 mm., R= 2.7 + r; breadth of 

 ray at base, about 35 mm. Disk large, rays fairly broad at base, 

 tapering to a pointed extremity. Pseudopaxillas very small, well 

 spaced, with 4 to 6 small spinelets; inferomarginal plates prominent 

 with numerous spinelets increasing very rapidly in size toward the 

 inner or lower end of the compressed, transversely oriented tabulum 

 or pedicel; distal marginals with mostly large spinelets only; furrow 

 spines 5 or 6, rather long; subambulacral spines 5 to 7, subequal in 

 length to furrow spines, but heavier; the inner end of the transverse 

 comb is turned aborad, and the innermost spine is shorter than the 

 second; superomargmal paxillse small, alternating with the infero- 

 marginals. Resembling somewhat S. paxillatus, but with more 

 numerous furrow spines, less conspicuous subambulacrals, heavier 

 inferomarginal spinelets, less conspicuous superomarginals, and 

 fewer paxillar spinelets. 



Type.— C^t. No. 32647, U.S.N.M. 



Type-locality.— St&tion 5654, Gulf of Boni, Celebes, 805 fathoms; 

 bottom not recorded. 



This species is allied to S. paxiUatus Sladen, but probably not very 

 closely, while it also shows some resemblance to -S'. horealis Fisher, 

 although it is not at all closely related to this form. The following 

 differences separate tropicus from paxiUatus. In tropicus the paxillae 

 have fewer, relatively coarser spinelets; marginal plates lower, with 

 conspicuously heavier spinelets at the inner or lower end than at the 

 upper or outer, and distal marginals occupied almost entirel}^ by a 

 relatively few large spinelets (somewhat as in 8. horealis); in S. 

 paxiUatus the inner marginal spinelets are only a little larger than 

 the outer and the armature of the distal marginals does not differ 

 materially from that of the proximal ; in tropicus the superomarginals 

 are lower and less conspicuous, the furrow spines more numerous 

 (5 or 6 instead of 3 or 4) and in large specimens the subambulacral 

 spines are decidedly less prominent (subequal to furrow spines). 

 S. tropicus differs from S. horealis in having less prominent marginal 

 plates and much more numerous and smaller marginal spines, dis- 

 tinguishable superomarginal plates, more numerous and longer 

 furrow spines, and more numerous and longer subambulacral spines. 

 S. regularis Sladen has larger and more widely spaced paxillse, more 

 prominent marginal plates, and the subambulacral spines form a 

 straight series. S. suharcuatus Sladen has fewer inferomarginal 

 spines (10-12), fewer furrow spines (3 or 4), and fewer oral and 

 suboral spines. S. torulatus Sladen has less prominent, actinally 

 situated marginals, with subequal spinelets, shorter furrow spines, 

 fewer subambulacral spines in a straight series, smaller actinal inter- 

 radial areas, and slightly more numerous abactinal paxillar spinelets. 



